The invention relates in general to the field of tape heads and apparatuses equipped with tape heads for writing to (and reading from) a magnetic tape.
Various data storage media or recording media such as magnetic tape, magnetic disks, optical tape, optical disks, holographic disks or cards, and the like are known which allow for storage and retrieval of data. In particular, in magnetic media, data are typically stored as magnetic transitions, i.e., they are magnetically recorded in the magnetic layer of the media. The data stored is usually arranged in data tracks. A typical magnetic storage medium, such as a magnetic tape, usually includes several data tracks. Data tracks may be written and read individually, or sets of data tracks may be written and read in parallel depending. Transducer (read/write) heads are positioned relative to the data tracks to read/write data along the tracks. To this aim, a tape drive head must locate each data track and accurately follow its path. To achieve this, servo techniques have been developed which allow for a precise positioning of the head relative to the data tracks. One such technique makes use of servo patterns, that is, patterns of signals or recorded marks on the medium, which are tracked by the head. The servo patterns are recorded on the recording medium such as to provide a position reference for the data tracks. In other words, a servo reader reads a servo pattern, which is then interpreted by a servo channel into a position error signal (PES). The latter is then used to adjust the distance of the servo head relative to the servo pattern and thereby ensure a proper positioning of the transducers with respect to the set of data tracks.
Continued progress in recording areal densities is contingent on the ability to ensure optimal write quality, i.e., to imprint the media so as to maximize the readback signal-to-noise ratio for otherwise fixed recording conditions (e.g., material properties of the media, reader element, and recording geometry). Features of the imprint which influence this quality are notably: the degree of saturation of the media between transition walls, the shape of the transition walls (straight, vertical walls are preferred to curved or inclined transitions), and the sharpness of the transition wall.